Disabled railway vehicles often can not be repaired at the location where the disability occurs or is first noticed. This is partly because the presence of a disabled vehicle on a track disrupts other train service in or through the area of the disability. Therefore prompt removal of the disabled vehicle is essential to the continued efficient operation of a large portion of the railway system. Additionally, the repair often requires specialized equipment and personnel that cannot readily be transported throughout an entire system to perform repair work. Furthermore, space limitations and safety factors very often preclude on site performance of repair work. For example, in many railway systems a large percentage of the trackage is either in tightly confined tunnels or on elevated structures. In either of these situations, the performance of extensive repair work is not feasible. On site repair work is even less realistic if the repair requires the use of welding or cutting equipment. Specifically steel dust, lubricants and debris often found adjacent to tracks can cause fires with extensive damage to nearby power, communication and signal lines being likely.
A particularly troublesome type of railway vehicle disability is one in which the wheels of the vehicle are rendered completely or partly inoperative. For example, a wheel may become fractured as a result of being subjected to heat or stresses over an extended period of time. In many such instances, one or more of the railway vehicle wheels is shattered into several distinct pieces. A similar disability to the train wheels is attributable to locked pinion gears. The locking of the pinion gear effectively stops the associated wheel or wheels from rotating. This failure may occur several vehicles away from the driver or engineer of the train who will be completely oblivious to the inability of certain wheels to rotate. These non-rotating wheels can be dragged along the track for many miles. This frictional interaction between the non-rotating wheel and the track will rapidly cause the wheel to wear into a noncircular configuration.
Attempts to move a noncircular wheel along a track is likely to cause major damage to sections of the track and related equipment adjacent thereto. For example, the switch points and other crossovers are specifically designed to accomodate the rolling movement of a nearly perfectly round wheel. The sliding movement of a noncircular object into these switch points can cause significant structural damage which can be attributable to subsequent derailments. The probability of damage resulting from the impact of the noncircular wheels to a switch point or the like can be appreciated when it is considered that a railway vehicle may weigh more than forty tons, and the vehicle may be traveling fifty miles per hour. Noncircular wheels also can damage structural or electrical equipment adjacent to the rail. For example, as the wheel assumes a noncircular configuration, the degree to which the flange of the wheel extends below the top riding surface of the rail increases. In extreme instances, the flange of a noncircular wheel will contact and break an adjacent structure.
A railway vehicle typically is mounted on a pair of separate trucks. Each truck generally includes a unitary frame onto which two axles and two pairs of wheels are mounted. Each axle and its associated wheels typically defines an integral structure that can not readily be disassembled into its parts. Consequently a broken or disabled wheel can not be removed and replaced by a spare, as might be done with an automobile.
In the past, the movement of vehicles with broken or non-rotating wheels has involved the placement of the wheels into a non-rotating position and the subsequent dragging of the disabled vehicle along the track. The disabled wheels have been placed in a non-rotating position either by welding the wheel to a fixed member or by cutting holes in opposite wheels and extending a locking bar therethrough. As noted above, this cutting and welding is known to present a significant safety hazard in many railway system environments. After the wheels have been suitably locked into a non-rotating position, the entire portion of track intermediate the point of disability and the repair shop is lubricated to facilitate the non-rotating movement of the disabled wheels, and to reduce the chance of damage to special work such as switch points. This lubrication of the tracks has been a slow labor intensive task. In many instances the section of track to be lubricated would extend twenty or more miles. Furthermore, to insure the safe stopping of trains that follow the disabled train it has been necessary to either sand the lubricated tracks or otherwise remove the lubrication. This also has been extremely time consuming and labor intensive.
Attempts to develop improved equipment and procedures for removing disabled vehicles have not been particularly successful, especially in the older urban systems where disabilities are most prevalent. Specifically, in these older systems the clearances in many tunnels, trestles and bridges may be no more than a few inches. Consequently the possibility of using additional equipment had long been thought of as being unavailable.
In view of the above, it is an object of the subject invention to provide an apparatus for facilitating the removal of disabled railway vehicles.
It is another object of the subject invention to provide an apparatus that can quickly be mounted to the disabled vehicle to minimize disruption to the railway system.
It is an additional object of the subject invention to provide an apparatus that can be employed to move a disabled railway vehicle along closely confined sections of track.
It is a further object of the subject invention to provide an apparatus for moving a disabled railway vehicle that does not require the use of welding or cutting equipment for proper installation.
It is still another object of the subject invention to provide an apparatus for moving a disabled railway vehicle that can be adapted to a wide range of vehicle types.